优质解答
I am / become expert at / in maths.
I am an expert at / in maths
I'm skilled at / in maths.
I'm good at maths.
I do well in maths.
I am / become expert at / in maths.
I am an expert at / in maths
I'm skilled at / in maths.
I'm good at maths.
I do well in maths.